sickliness

noun

1. (uncountable, usually)The state or characteristic of weakness, incapacity, or physical distress due to poor health, especially of a chronic nature.

   “I do beseech your majesty, impute his words To wayward sickliness and age in him.”

   “Gradually it gave place to a smile; a feeble, helpless, melancholy smile; bland, almost to sickliness.”

   “My devotions were disturbed with a feeling of languor and sickliness, and the tormenting fear of its becoming worse: and a depressing headache was generally my companion throughout the day.”